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<title>简单的HTML+CSS+JS</title>
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  <p>第一步 加上CSS叠层样式style=""</p>
  <div style="width:80px; height:80px; border:red dashed 2px; background:url(前端自编内容/DIV+CSS布局实战mix/flower-1.jpg)">aaa</div>
  <p>第二步 在div标签内直接加上JavaScript效果。（js的格式）注意是赋值号=不是分号：，且必须有单引号</p>
  <div onClick="this.style.width='180px'; this.style.height='112px'" style="width:80px; height:80px; border:red dashed 2px; background:url(前端自编内容/DIV+CSS布局实战mix/flower-1.jpg)">aaa</div>
  <p>第三步 在style=""属性加入transition，达到过渡效果</p>
  <div onClick="this.style.width='180px'; this.style.height='112px'" style="width:80px; height:80px; border:red dashed 2px; transition:2s; background:url(前端自编内容/DIV+CSS布局实战mix/flower-1.jpg)">aaa</div>
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